Inventories - Schedule of Inventories (Detail) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Finished goods	$ 68,303	$ 40,682
Work in process	19,000	18,000
Rental units	62,531	62,531
Parts and subassemblies	666,729	603,443
Total cost	816,563	724,656
Less: reserve for rental units	(22,772)	(17,542)
Inventories, net	$ 793,791	$ 707,114

Inventory rental units.

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- Definition

Inventory reserve for rental units.

+ References

No definition available.

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- References

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- Definition

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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-Publisher FASB
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-Section 45
-Paragraph 1
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- Definition

Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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- Definition

The aggregate carrying amount as of the balance sheet date of items held by the entity which are partially completed at the time of measurement and unprocessed items that will go through the production process and become part of the final product. Includes supplies used directly or indirectly in the manufacturing or production process. This element may be used when the reporting entity combines work in process and raw materials into an aggregate amount.

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